An Express Train Travels 464 Mi in the Same Amount

question 19

Multiple Choice

An express train travels 464 mi in the same amount of time it takes a freight train to travel 240 mi. The rate of the express train is 28 mph faster than that of the freight train. Find the rate of the express train.

• A) 58 mph
• B) 66 mph
• C) 64 mph
• D) 65 mph
• E) 59 mph

---

Definitions:

Marginal Cost

The raised expense resulting from the production of one additional product or service unit.

Optimal Amount

The most efficient level or quantity of a good or service to achieve a specific goal or maximize utility.

Concentration Ratios

Measures that indicate the degree of market concentration by showing the market share of the largest firms in an industry.

Inverted-U Theory

A hypothesis that suggests there is a relationship between the level of some activity and the effect it has on performance, which looks like an inverted U, indicating optimal performance at an intermediate level of the activity.